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XmlChan - I/O Channel using XML to represent Objects

Description:
A XmlChan is a specialised form of Channel which supports XML I/O operations. Writing an Object to an XmlChan (using AST_WRITE) will, if the Object is suitable, generate an XML description of that Object, and reading from an XmlChan will create a new Object from its XML description.

Normally, when you use an XmlChan, you should provide "source" and "sink" routines which connect it to an external data store by reading and writing the resulting XML text. These routines should perform any conversions needed between external character encodings and the internal ASCII encoding. If no such routines are supplied, a Channel will read from standard input and write to standard output.

Constructor Function:
AST_XMLCHAN
Inheritance
The XmlChan class inherits from the Channel class.
Attributes
In addition to those attributes common to all Channels, every XmlChan also has the following attributes:

Functions
The XmlChan class does not define any new routines beyond those which are applicable to all Mappings.


next up previous 264
Next: ZoomMap - Zoom coordinates about the origin
Up: AST Class Descriptions
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AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk

Copyright (C) 2009 Science \& Technology Facilities Council